Matt Mohn, a freshman at Duke University, was walking past a Black History Month bulletin board in his dorm last weekend when he noticed something taped next to a photo of George Floyd.

As he got closer, he realized it was a printout of Floyd’s toxicology report from his autopsy. And on the sheet of paper was a handwritten note suggesting that Floyd was to blame when he died in Minneapolis police custody last spring after an officer knelt on his neck for more than nine minutes.

“Mix of drugs presents in difficulty breathing! Overdose? Good man? Use of fake currency is a felony!” read a note written in pink.

Mohn, 19, said he was shocked by the printout, calling the incident, which was first reported by the Duke Chronicle, a “racist” attack.

“I was really incredulous that someone would actually go to the effort of finding the report in its original form,” Mohn said. “It seemed almost more audacious than just writing a slur or putting up something more overtly hateful.”

Now, school administrators and campus police are investigating the incident as a possible violation of the school’s anti-harassment and discrimination policy, school administrators announced in an email to students this week. The school referred to the note as an “anonymous act of bias.”

“If Duke students are found to be responsible for this act, the Office of Conduct and Community Standards (OSCCS) will issue sanctions to the responsible student,” Associate Vice President for Student Affairs and Dean of Students John Blackshear and OSCCS Senior Associate Dean and Director Jeanna McCullers said in the email.

The school’s investigation comes as Floyd’s case has reemerged in the headlines as a judge this week finished selecting a jury for the trial of Derek Chauvin, the former Minneapolis police officer charged in his death.

Mohn found the note on Saturday inside a dorm that has a hallway bulletin board commemorating Black victims of police violence, including Philando Castile and Breonna Taylor. Just like Floyd’s post, each picture was accompanied by a summary of the incident related to their death.

Floyd, 46, was killed last May after police detained him outside a grocery store for allegedly having a counterfeit $20 bill. He was handcuffed facedown when Chauvin knelt on his neck as Floyd cried, “I can’t breathe.” An autopsy report found that Floyd died of cardiopulmonary arrest and neck compression, The Post previously reported. An independent autopsy commissioned by Floyd’s family found that he died of “asphyxiation from sustained pressure” after being pinned down by his neck and back.

Mohn, who is White, told The Post that the bulletin board had never been vandalized since a resident assistant put it up in February — so he was surprised to see the note this weekend. He said the point of the addition was obvious.

“The entire message was that he was responsible for his own demise,” Mohn said. “That because he tested positive for drugs or because he had one $20 bill that was counterfeit that he deserved to be executed. I think it was racist in a way that absolved the White police officer that had been kneeling on him.”

Mohn said he took a picture of the printout and sent it to his building’s group chat. A resident assistant who saw the message removed the printout minutes later, he said.

Later that afternoon, according to Mohn and the Chronicle, students met with Blackshear to discuss the incident. Michael Manns, a freshman who lives down the hall from where the flier was found, told CNN the incident left him “terrified.”

“I remember shaking in that moment,” Manns, who is Black, told CNN. “That happened right down the hall from where I sleep, from where I’m supposed to be safe. … The thought that it could be someone I’ve lived with all these months really terrified me.”

On Tuesday, school authorities sent an email recounting the incident and announcing an investigation. The university added it would not disclose the names of anyone involved in the incident if investigators learned they were Duke students, citing student privacy laws.

“Any incident that is motivated in whole or part by an individual’s race, warrants ‘acceleration’ or elevation of sanctioning due to the impact on the community,” the email stated, noting that if no students are found to be responsible, the university is expected to announce the results of the investigation by April 15.

Mohn said he has one message to whoever hung the flier on the board: “Think about how your Black neighbors that live in the building would feel about having to look at that in the place they live.”